The authentication of persons using biometric input data is growing in importance. The authentication can be used in order to grant a person access to a physical space, e.g., an office or a mode of transportation, or to a virtual space, such as a financial account, or to grant the person the right to make a monetary transaction or to use a device such as a personal communication device, as a few non-limiting examples. It is therefore important to reduce an occurrence of erroneous and fraudulent biometric authentications, such as those based on the recognition of an image (e.g. a facial image) of an authorized person.